Wide Mouth Fan Duct for Ultimaker

This delivers more air than my previous fan duct.
Suitable for V2 Nozzle.
Clearance is 3mm to platform and 2.5mm to heater block.
May be suitable for dual extruders (Untried yet)
Push on and Nut Mounted variety.
Updated Both Fan Ducts May 16/2013 (better wall thickness. Firmer fit for Push on Duct. Old one started slipping after a bit of use)
See http://www.thingiverse.com/thing:77107 for what looks to be a good improvement to my push on Duct.